The present invention generally relates to a selective call receiving apparatus, such as pager, having a display function.
In general, the selective call receiving apparatus incorporating the display function is so arranged that the message information received from a sender station is once stored in a memory unit for producing a reception alert signal and displaying the received message information.
Reference is made to FIGS. 15 and 16 of the accompanying drawings which illustrate information storage areas in a memory unit employed for storing the incoming message information in the prior art selective call receiving apparatus. The storage area under consideration is assumed to have eight memory locations or regions designated by numerals 21 to 28, respectively.
Referring to FIG. 15, the region 21 is destined to store therein the most recent incoming message information A2, and the region 22 is used to store the next recent incoming message information B4. In the similar manner, regions 23, 24, 25 and 26 stores message information A1, B3, B2 and B1 in the order of incoming sequence. The regions 27 and 28 are not yet occupied with any message information. In FIGS. 15 and 16, reference characters A and B represent the message information received for every selective calling signal and the affixed numerals 1, . . . , 4 indicate the order in which the associated incoming message signals have been received for every selective calling signal.
FIG. 16 is a view for illustrating how the new incoming message information B5 is stored starting from the storage state illustrated in FIG. 15. As will be seen, the new incoming message information B5 is stored in the location or region 21, while the information A2, B4, A1, B3, B2 and B1 stored till then in the regions 21, 22, 23, 24, 25 and 26, respectively, are transferred to the regions 22, 23, 24, 25, 26 and 27, respectively.
FIG. 17 of the accompanying drawings shows the state of the memory unit in which all the regions 21 to 28 have the message information stored therein. When new incoming message A4 is received in the storage state illustrated in FIG. 17, the new incoming signal A4 is stored in the region 21 as shown in FIG. 18, while the information stored in the regions 21 to 27 is transferred sequentially to the subsequent regions 22 to 28, respectively, wherein the oldest information B1 stored till then in the region 28 is erased.
In the prior art memory system of the arrangement in which the message information is stored simply in the incoming sequence of the selective calling signals, as described above, the incoming message information even of a significant value is undesirably erased at an earlier time point, when a new incoming message is stored in the aforementioned memory unit of the state in which all the memory locations or regions have been occupied with the incoming message information stored therein, thus giving rise to a problem.